Lord Coe was 14 when he gave his first interview. "It's an awful thought," he grins, pretending to shudder, "but I've probably been interviewed on a regular basis for 42 years." Communication has become, he says, the single most important part of his job. "It's about being able to create a vision and talk about it. The biggest fragility in a project is often just the inability to be able to explain to people why you are doing it, and when you're going to do it, and what's going to happen." He's right, of course, and as the London Olympics were such a hit, you would think that he must be a brilliant communicator. I did – until I picked up his autobiography.

Seldom can a memoir have revealed less about its author – or less of what anyone might actually want to know, anyway. If the interminable minutiae of obscure athletics meetings is your thing, then, to be fair, Running My Life may be for you. But if you are curious to know what Sebastian Coe was like as a child, what athletics meant to him, how he felt about his arch rival Steve Ovett, why he went into politics, or what it felt like to be in charge of the Olympics, it will leave you none the wiser. The pages are bleached of all emotional meaning, and how the author got through them all without boring himself to death is a mystery. Like me, you might conclude that he has to be much more illuminating in person. If so, you would be wrong.

Coe is perfectly pleasant – affable, polite, professional – and gives no indication of deliberately trying to say nothing. On the contrary, he digests each question with quiet relish, before launching into probably the longest answers I have ever come across. More than once, I catch myself starting to nod off, and have a panicky moment trying to work out what I have missed, but he is too busy droning on to notice. It is like a rare form of conversational colour-blindness. Offered a choice between saying something diverting or something dreary, Coe plumps unerringly for the latter, at great length. It is as if he were set on trying to filibuster his own interview.

The odd thing is that, having had not one but three incredible careers, Coe ought to be riveting. In 1979, the young middle-distance runner broke three world records in just 41 days, becoming the poster boy of British athletics in the 80s, electrifying the Moscow and LA Olympics with his rivalry with Ovett. After retiring from athletics at 34, Coe was immediately selected to stand as a Tory MP, serving one parliamentary term, latterly as a whip, before losing his seat in 1997, only to be appointed William Hague's chief of staff. Hague's 2001 defeat brought Coe's party political career to a close, but within months he was working for the Labour government, advising on London's Olympic bid. The bid still wasn't looking too promising in 2004, when Coe became Locog's chairman. Eight years on, he is a national hero, rightly feted for a historic triumph that took the whole world by surprise. By anyone's standards, his achievements are astonishing.

"I always remember the 10th of September being the first morning, virtually in a decade, I woke up without thinking of winning a bid or delivering a game. Crucially, I'm not waking up each morning thinking: 'Oh my God, I've got security transports, licence agreements, the work over what the customer experience is going to be like, whether the coffee is going to be any good in the Olympic village' – you're not in that mindset. It is very similar to finishing a four-year competitive cycle."

When Coe used to compete, he was too absorbed in winning races to have any idea what the Games meant beyond the stadium.

"It's only when you get home and back into the sort of normal day-to-day stuff, that people stop you in the street and say: 'Wasn't that unbelievable?' I'm in that sort of phase now where I'm only really beginning to understand what the Games meant for people who come up to me – and it happens a lot, a lot. People do come up and they just say, 'It was extraordinary' and 'Thank you to your teams.' A guy this morning – a guy in a taxi – he said: 'I went to the Games. We got four tickets in the men's 100 metres. We were really lucky.' But then he said: 'Do you know something? If I'm being honest, I preferred the Paralympic dressage.'

"These are the conversations I've had and they're lovely conversations and they just help paint a bit more of a picture, because at Games time you're thinking about nothing other than the next challenge, the next message about a team that didn't quite feel that the carrots were cooked properly in the Olympic village. So the past few weeks has been a sort of – I suppose it's the right word, really – it's been a sort of recollection by osmosis. People are painting the picture that you didn't really see at the Games, and it's exactly the same as being a competitor."

Coe is still working full-time on the Olympics, overseeing legacy projects. I ask if we will ever know if the Games' economic legacy repaid their astronomical cost, but Coe doesn't measure success in terms of balance sheets.

"I'm a great believer in big events attracting big names and role models, and I think young people tend to take up sport because of what they witness at that level, rather than nationally endorsed projects saying: 'Unless you all start running three times a week you're going to drop dead with a heart attack at the age of 40.' I don't think those work. I will go to my grave believing that participation is best driven by the well-stocked shop window. I got involved with this project 10 years ago because I could not see a better opportunity in my lifetime for creating a step change in the way sport is delivered, in the way young people see sport, and in the way people could engage with the disability agenda."

Coe has been politically active since his time at Loughborough University, where he joined the Young Conservatives, but I'm still not clear about his ideological motivation. What exactly does he believe in? He looks a little surprised. "I think I'm probably just an old-fashioned Tory. I don't wake up each morning trying to figure out what kind of Conservative I am; for me it's quite instinctive. I actually don't believe in big government and half the time I'm never quite sure I believe in government, generally."

But without government, I say, we wouldn't have had the Olympics.

"No, that is true. That is true."

By now you may well be thinking he doesn't sound all that dull. But these few nuggets are as good as it gets. To demonstrate just what a crashing bore he is, I would have to quote all the acres of tedium from which they were salvaged, running the risk of sending every reader to sleep. We owe Coe a national debt of gratitude for pulling off an Olympic games beyond our wildest dreams, but how he did it I do not know, because his leadership qualities are difficult to spot. Clearly they've got to be hiding in there somewhere, or London 2012 would not have happened – so instead I try reading between the lines, see if I can work out what he's like from all the things he neglects to mention.

Coe was born in 1956, one of four children. His mother was a glamorous half-Indian actor, and his father was a highly intelligent working-class engineer. His father's work took the family all over the country until eventually they settled in Sheffield, where Coe's athletic promise quickly began to define his adolescence. Applying the principles of engineering to the new discipline of athletics, Coe's father became his coach, mentor, psychologist and nutritionist – the dominant force in his son's life.

He is certainly the dominant presence in the autobiography, and the author has nothing but praise for his father's dedication. At one point his father even got hold of eastern European training manuals and had them translated so he could work out exactly what his son was up against.

"He was ferociously clever," Coe recalls proudly. "I mean ferociously clever. He could cut through the flab of an argument and, in training terms, he spent five or six years doing nothing else, other than understanding the nature of what it would take to get me to run two laps quicker than anyone else." But what was he like? "Very much warmer than people thought."

Coe has a maddening habit of alluding to criticisms or conflicts without ever addressing them. As the book goes on, it becomes apparent that most of the athletics world, and much of the media, regarded his father as a bit of a tyrant – a loner, arrogant and over-controlling. But we never find out why, nor does Coe ever explain why they had got him wrong.

Coe's mother barely gets a mention, though there is a revealing line about watching her cheer him from the stands. "Watching her son break a world record might go some way, I hoped, to make up for all she'd put up with along the way." What did he mean?

"Well, she was a remarkable woman, and the great thing she did, at key moments, she did gently remind me that there is a little bit more to running two laps quicker than the next person. She was always a balancing influence, and without wanting it to sound too managerial, the management of a family around one of her children not being able to eat until nine o'clock most nights, travelling all the time – well, of course, it's a fairly selfish existence, so making sure my brother and sisters didn't feel neglected." They get even less of a look-in than his mum, so I ask if there was sibling resentment. "Er, if you're being honest, probably. I think it's human nature."

What about Ovett? "Right," Coe says, stiffening slightly. "The truth is that I didn't really know him. But I like him. He's a really good guy." Yet Coe writes: "Steve was playing up to his role of bad-boy in the devil-may-care way he finished his races, waving to the crowd or running across the track, adding unnecessary seconds to his time but endearing himself to the general public, who always love a maverick and slightly despise the boy with the clean handkerchief." He writes of beating Ovett in 1989: "While I was being interviewed on air about exactly what had happened, Steve was trackside in emotional turmoil, saying: 'They got me here on false pretences and lied to a lot of other people.' Upstaged to the end." In each passage, it's the barbed payoff line that says a lot about Coe's true opinion of his charismatic rival's popularity.

It is clear from the book that Coe thinks of himself as decent, unassuming, straightforward and hard-working – an old-fashioned gentleman to whom good manners matter more than gold medals. He volunteers little evidence to the contrary. Nevertheless, every now and then, rather reluctantly, he will mention odd things so incompatible with his self-image that you wonder how reliable it really is.

For example, when Coe confounded sports reporters' doubts by winning in LA in 1984, he turned to the press box, shook his fist and screamed: "Who says I'm finished now?" Where did that come from? He had never mentioned any fury towards the press. Likewise, he tells us about falling in love with Nicky McIrvine, an equestrian eventer, getting married and having four children together. Later, he explains their subsequent divorce as a casualty of Westminster's impossible working hours. Only much later, and almost by the bye, does he mention his extra-marital affair. Even then he makes it sound pretty unimportant, when in fact it went on for a decade. He doesn't even mention his mother's death except as a belated afterthought.

At various points in the book, he alludes to a widespread impression of Coe as arrogant, aloof and rather unlovable – the Steve Davis of athletics. The public loved to see him win, but were less keen to fell in love with him, and I think I detect a faintly aggrieved sense that the world was never really on his side.

"No ... I don't think ..." Coe hesitates and stutters. "I think if you are quite single-minded about what you are doing ..." Suddenly, he sounds defensive. "Look, throughout my career I was always a member of an athletics club. I always trained and competed for an athletics club, even as a double-Olympic champion. I think it's probably – I think there are … Not that I think it, being honest, not that it really bothers me. But I do think that people that are really focused probably give out those vibes when they're not meaning to be aloof, but that it's just what they do. When I was in a racing situation, it was the most important thing in my life. You train for 10 years, you run thousands of miles, you do take it quite seriously."

The talk in political circles is now about Coe succeeding Boris Johnson as the next Tory candidate for mayor of London. He would be uniquely well qualified, of course – but is he someone the capital could fall in love with? Like his father, he seems to have taken the principles of one discipline and applied them to another, and what he did with London 2012 was astonishing. But it doesn't necessarily make him very endearing.

At moments I wonder whether Coe himself might be finding his new national treasure identity a bit uncomfortable. It is certainly unfamiliar. On the track, the people's champion was always Ovett, never Coe; in politics, he represented his party through its darkest ever decade. And up until late July, popular attitudes towards the Olympics tended to range from ridicule to resentment. Now, all of a sudden, everyone loves him. So what will he do next?

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